On Wed, May 27, 2020 at 5:38 PM Gene Heskett <ghesk...@shentel.net> wrote:
> On Wednesday 27 May 2020 20:10:44 Chris Albertson wrote: > > > By total coincidence, I just made both. I needed 30T, 40T, and 60T > > pulleys. I tried printing them and they fail after a while. The > > plastic simply will not hold the set screw then they slip on the > > shaft. The big thing is if the motor gets warm it heats the plastic. > > The solution has to print the pulley as the thin ring. My 30T puley > > has a 20mm hole. Then use the lathe to make a 20mm OD bushing with > > two set screws 90 degrees apart. I make this with steel. The > > pulley-ring is press fit to the steel bushing using 5 minute epoxy. > > OK, you ask "How strong can plastic teeth be?" the answer seems to be > > "stronger than the rubber teeth on the belt." The part of the pulley > > that needs to be strong is the hub and that is now steel. Making a > > center bored cylindrical bushing is a very easy job. I made a few > > and this method turned out the simplest and best. Make the ring > > really thin so as to make the bushing as big as you can. > > > > I just returned from riding my bike for a few hours and notice my > > NEMA23 mount plate is 80% finished. I'm still testing if these can > > be made with plastic. I think so if about 6mm thick I'll know soon. > > I have a test setup to check for flex in the plate. > > > > I'm working on a plan or "kit" to convert an HF mill to CNC using > > way-cheap plastic parts (< $20 material cost) and minimal machine > > work. I'll publish the design files after it works. I've had to > > redesign/remake some parts 3 or 4 times but it comes out more simple > > each iteration > > I'd like to see if I could convert this 6040 into a printer, precisely so > I could do something along those lines but in looking around for a > printhead, it seems the drive is much lighter so smaller motors can move > it faster, and never the twain shall meet. Trading a 3kg 24k spindle > motor out for a printhead the might weigh 5oz is quite a change. I > could buy another printer, but where I'd have to set it up has no AC. > And good results seem to be quite temp dependent. So I get that stuff > from fleabay, and wait, and wait, and wait. Thats frustrating too. > > So who makes the best printer for stuff like this, at an affordable > price? > Most people are recommending the "Ender" brand printer for your use-case. This is an open-source design that uses industry-standard parts so future maintenance should not be to much of an issue. If you print with PLA plastic, it is bomb-proof simple and temperature, and so on does not matter. My printer is an Anet "A6" and I paid about $185 for it. It looks cheap because the frame is made from laser-cut acrylic plastic. But acrylic is strong and rigid and works well. The Ender has a metal frame and is slighter better. But be-warned, a printer is like a CNC mill in that that parts it makes have to be carefully designed but unlike a mill, there is no hope of ever writing printer G-code by hand, it is far to complex. Plastic can be strong if you puff up the thickness and make all the sides round. You tend to print parts with solid shell and a foam-like interior. amazon.com/Comgrow-Creality-Ender-Aluminum <https://www.amazon.com/Comgrow-Creality-Ender-Aluminum-220x220x250mm/dp/B07BR3F9N6> This is the one I have. The price has gone up because those selling cheap when broke. amazon.com/Precision-Desktop-Printer <https://www.amazon.com/Precision-Desktop-Printer-Assembly-Cleaning/dp/B01N5XV5NU/ref=sr_1_2?dchild=1&keywords=anet+a6+printer&qid=1590632711&s=industrial&sr=1-2> The plastic costs about $22 per Kg. I use "hatchbox" band but I'm sure others work too. Just do start with PLA and likely you stay with it. amazon.com/HATCHBOX <https://www.amazon.com/HATCHBOX-3D-Filament-Dimensional-Accuracy/dp/B00J0GPC80/ref=pd_sim_328_5/140-9661733-2175833?_encoding=UTF8&pd_rd_i=B00J0GPC80&pd_rd_r=c9f25db5-27c5-4c4e-b5fb-62dd9b9c3b12&pd_rd_w=5vegT&pd_rd_wg=AfyjI&pf_rd_p=6f740e39-0c25-4380-8008-7a4156dab959&pf_rd_r=W6FB1TGW7SX8KDWJ04KR&psc=1&refRID=W6FB1TGW7SX8KDWJ04KR> 1 Kg is a lot. I printed a mod 2, 120 tooth gear that is about 5" diameter and 1" face width. It is a really big gear. It used about 160g of plastic. > > On Wed, May 27, 2020 at 2:06 PM Gene Heskett <ghesk...@shentel.net> > wrote: > > > On Wednesday 27 May 2020 00:51:57 Gene Heskett wrote: > > > > On Tuesday 26 May 2020 19:45:10 Chris Albertson wrote: > > > > > On Tue, May 26, 2020 at 3:01 PM Gene Heskett > > > > > <ghesk...@shentel.net> > > > > > > > > wrote: > > > > > > Those closed loop motors and controllers have arrived, and I > > > > > > puzzled by a total lack of docs other than the u-step ratios > > > > > > printed on the cover. Thats covered by dip sw1-4, but its a 6 > > > > > > pos switch, and 5 & 6 are in Chinese pictograms. > > > > > > > > > > I'm following this because, as said, I plan on doing the same. > > > > > However I always read the docs BEFORE buying, no docs, I don't > > > > > buy. > > > > > > > > > > Post a photo of the Chinese characaters, I have someone here > > > > > fluent in Chinese. Also you can try Chinese OCR and then apply > > > > > Google Translate. > > > > > http://www.i2ocr.com/free-online-chinese-traditional-ocr > > > > > > > > I found out what they do, one is a direction reverser, the other > > > > makes it open loop. Suits me anyway. I'll get one of those > > > > supplies and one of these on the same table and play with a > > > > function generator tomorrow, claims to be good for 200 khz steps, > > > > and has divisors out the yang, so it ought to be a dropin except > > > > for the mounts and shaft sizes so I'll need to find some timing > > > > pulleys and belts. And a nema 23 mount since that 1600 oz/in on > > > > the Z now is a nema 34 mount. An see if there is room enough > > > > behind the apron for one of them, its 124mm long in which case > > > > I'll order another for the indexer and put both of these on the > > > > Sheldon. > > > > > > Shot down there, its around 4mm too long to clear the bed. > > > > > > As it runs, the 800 or 1000 divisor seems to be the smoothest, > > > either one getting to 2500+ revs, 800 stalling, 1000 dieing because > > > of slow opto's at about 220 kilohertz. Either way plenty of turn the > > > house around torque, so I'm suitably impressed. Now I need a 10mm > > > belt pulley with 30 teeth and a motor mount for a nema 23. The > > > trick is finding both on this side of the pond... > > > > > > Thanks All > > > > > > > That 8 lead nema 24 on the x is slow, stalls at > > > > about 30 ipm. even when set as 4 wire parallel and all the amps a > > > > 2m542 can do. Even then it runs cooler than steppers usually do. > > > > The x belt tensioner is drilled for a 23 and then the holes were > > > > moved enough for the 24. > > > > > > > > > My guess about the cable length mismatch is that the seller you > > > > > bought this from gathers parts and packages them and this motor > > > > > was made for a use case that did not include this controller. > > > > > > > > The motor and encoder look to be an integrated unit. So I'll have > > > > to splice it, or pull the cover and see if its easily replaceable > > > > with a smallish 18 or 20 gauge line cable. Lots of layup stuffing > > > > on this one to get to a matching cable jacket size, the wire gauge > > > > itself isn't impressive at all. At its peak of 4 amps a coil, that > > > > cable WILL heat. Not badly, but detectable. > > > > > > > > > When googling for the instruction, look for related controllers > > > > > as I'd bet the firmware was written to run on many different > > > > > sizes of controllers, not just the one you have. Many of these > > > > > are Leadshine clones so look at Leadshine web site. > > > > > > > > Thanks Chris, stay well. > > > > > > > > Cheers, Gene Heskett > > > > > > Cheers, Gene Heskett > > > -- > > > "There are four boxes to be used in defense of liberty: > > > soap, ballot, jury, and ammo. Please use in that order." > > > -Ed Howdershelt (Author) > > > If we desire respect for the law, we must first make the law > > > respectable. - Louis D. Brandeis > > > Genes Web page <http://geneslinuxbox.net:6309/gene> > > > > > > > > > _______________________________________________ > > > Emc-users mailing list > > > Emc-users@lists.sourceforge.net > > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > Cheers, Gene Heskett > -- > "There are four boxes to be used in defense of liberty: > soap, ballot, jury, and ammo. Please use in that order." > -Ed Howdershelt (Author) > If we desire respect for the law, we must first make the law respectable. > - Louis D. Brandeis > Genes Web page <http://geneslinuxbox.net:6309/gene> > > > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > -- Chris Albertson Redondo Beach, California _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
